Tube-mill grinder.



WITNESSES I I nwE/mn W. MAIN. V TUBE MILL GRINDER. grrmoumn. nun ARE. 3, 1912.

1 043 855; I Patented Nov.-12,19 12.

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WILLIAM MAIN, F PIERMON T, NEW YORK.

iii- 9 Specification of Letters Patent.

TUBE-MILL GRINDER.

Patented-"Nov. 12, 1912,

Application filed April .3, 1912. Serial No. 688,272."

-T0 "a j Be-iit known that I,

.-Piermont, eountylof- Rockland,'f State of New York,-lfave=made' certain new and use- 1 ful Inventions Relating to Tube-Mill Grindtionatakemin connection with the accom- -i rmg' 'd mngno 1 This--1nvention relates to grinders suitablefor' use in tube mills and the like, these flattened'lenticular form, the convex facesiof the gI'iIIdGI'S COIDPI'l SlDglarge rasurje large" area" grinding contactbe- I these grinders-when used undertube conditions,- I the; accompanying drawing showing in 'ative. embodimentsof this invention, Figs a'face View of one form of grinder. is an edge view of another form, and Fig 3qthecorres'ponding face view. Fig. 4

" a5 showsa blank from which may be formed individual grinders as are shown in Fig. l. ig;',5 i's a .-'-face.view of another form of grinder; and Fi 6an edge view thereof.

These metallic grinders are preferably .30"given a thin 'lenticular.form so as to have -theirfflattened convex grinding" surfaces .coin-priseport-ions having large radius cylinfldi'icali surfaces or large radius spherical elements" to insure correspondingly large area .hbzgfihding contact betweenthe grinders which may have eit-her circular or substantially polygonal or rectangular con-vex faces with rounded corners. Fig. 1 shows one form [of'such' lenticular grinders, which may iiqbe provided with substantially rectangularconvex" faces having rounded corners such ras'fi 'andjcomprlse the large radiusicyhn- A .drical portions such as 1, 2, 3 and 4:, starting 'fro'mjthe rounded edges and meeting in the fifidiaglonal intersecting lines. 5, these cylinflgical: portions being, if desired, carried sharply into the rounded corners 6 so as to form the intersecting lines 7 in connection therewith, If desired, however, the grind- .w ers mayhave their corners rounded considerably more soas to have such decidedly roundedrcorners l0 -as shown in Fig. 3 and the substantiaclly cylindiical large radius portions between the dotted lines 14 may fiF'gradually merge into each other so as to make the convex faces 9 of these gr nders v .WILIJAM MAIN, a Y t niflfthe nited' States, and resident of ers, ofrwhichi-the following is a specificagrinders being formed of metal and having cylgindrical or spherical portions so asoi iiewhat diagrammatic way certain illus-.

more smoothly curved and somewhat more nearly a large radius, sphericalconvex surface, the edge 8 of this grinder being preferably rounded as indicated in, Fig. 2. It is of course understood that under service conditions the grinders tend to wear so as to smooth off all sharp edges so that the Sharp intersecting edges of Fig. 1- wbuld in the course of time be rounded offend make this form of the proach that shown in'Fig. 8.

grinders more nearly ap- These grinders are preferably made small, so as to lncr'easethe number of grinders and correspondingly increase the amount of grinding contact between their respective surfaces. under tube mill conditions, for instance. These lenticular grinders may with. 1 good results be between an inch and an inch and a-half or so across and have a thickness of a. quarter of an lnch or more.

.is indicated somewhat diagrammatically in Fig. 4. In that case a single row of these grinders is shown joined together along the thinned lines of severance l1 along which the grinders may of course be readily broken apart and if desired the edges may be somewhat. smoothed or rounded, although of course this is rapidly effected when the grinders are used in a tube or ball mill. By using the customary weight of these lenticular grinders in a tube mill fOr instance, the number of grlndlng contacts isgreatly increased and the convex form of their grinding faces secure sufficient intensity of grinding pressure to lnsure proper reduclng action, while at the same time the large radius of these curved grinding surfaces gives I These 1 grinders may be made 1n any desired way ample grinding contact to make the reduction eflicient.

Another form of grinder 1s shown 1n Figs.

5 and 6 as having substantially circular con vex faces 12 which may be composed of ai ai radius spherical portions, the grinder being preferably formed with a suitably rounded edge 13, and having a thickness of half an inch or so.

Having descrlbed this invention in con- "nection with a number of illustrative em- I: the lar convex faces having rounded corners and edges and comprising four intersecting 0011- l vex face portions of large radius to nsure claims.

bodiments, forms, proportions, materials and methods of manufacture, to the details of which disclosure the invention is not of course to be limited,fwhat is claimed as new vand what is desired 'to be large area grinding contact between the grinders under service conditions, -said grinders being about ,an inch and a half across and between about one-quarter and one-half of an inch thick.

2. The thin lenticular hard metallic grinders suitable for use in tube mills and '1 the, like and having substantially convex faces having rounded corners and edges and comprising a plurality of convex face portion's of large radius to insure large area grinding contact between the grinders under 1 service conditions, said grinders being be- I tween about an 111011 and an inch and a half across and between about one quarterand one half of an inch thick.

Witnesses:

HARRY L. DUNCAN, JESSIE KAY.

WILLIAM MAIN, 

